While they're not the best thing in the world they do work relatively well. Since they're amplified antenna's you have to have the amplifier turned on. I've forgotten to press the little button a few times.
If you had the amplifier on and it still wasn't working it may not be connected correctly behind the wallplate.
Salem 29RKSS Pushing a 2500 Mega-Cab CTD!
Gotta go campin!